package com.itheima.reggie.config;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest)servletRequest;
        HttpServletResponse response = (HttpServletResponse)servletResponse;
        //1.获取本次请求的uri
        String requestURI = request.getRequestURI();
        //1.1定义不需要处理的路径
        String [] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**"
        };

        //2.判断本次请求是否需要处理
        Boolean check = check(urls,requestURI);

        //3.如果不需要处理直接放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4.判断已登录直接放行
        if (request.getSession().getAttribute("employee")!=null) {
            log.info("用户已登录，用户登录的id为{}",request.getSession().getAttribute("employee"));
            filterChain.doFilter(request,response);
            return;
        }

        //5.如果未登录，返回未登录结果，通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    private Boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){return true;}
        }
        return false;
    }
}
